Post some pics! I have the eibach springs and plan on getting the Milano's also!
You probably will not have to buy arms. If you get a good alignment, you should be fine. Even if there is a little wear on your tires, it will not be much of a difference.
I got a good alignment, and I haven't seen any wear yet with my Eibach springs.
:welcome: to the site!!! and get us some pics!